Patent · US Expired

Method and apparatus for illuminating projecting features on the surface of a semiconductor wafer

US6547409B2 · kind B2 · utility

8Cited by
21References
35Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 12, 2001
Grant dateApr 15, 2003
Priority date
Expiry dateJul 6, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L2924/14
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

Plural light sources are provided for directing ring patterns of light toward at least one reflective bump formed on and projecting from a first wafer surface of a semiconductor wafer. The intensity of light from the light sources may be varied and may be varied independently of one another.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.